A wireless switched local area network (WLAN) utilizes a switch to transmit data between various network components. The switch may be capable of inspecting data packets as they are received, determining the source and destination device of each packet, and forwarding the packet appropriately. For example, a switch can send a broadcast packet to all the access points (APs) under its control to be broadcast to multiple client devices associated with those access points. The more access points used, the wider amount of area the network can cover. However, access points come in different configurations, some of which are more expensive, e.g. a “fat” access point with its own internal intelligent processing components, versus a lower cost “thin” access point (or access port) which only serves to transfer packets. Thus, thin access points may be used to provide a low cost way to extend an operating coverage area of the network. However, thin access points are equipped with less intelligent components than conventional access points, and therefore the switch must be able to perform the intelligence to make sure that packets are properly delivered to particular devices, such as devices associated in a virtual local area network (VLAN). In addition, since thin access points are low cost, they could be deployed in large numbers, and the switch will need to manage all of these many thin access points.
A VLAN is a logical subset of devices in one or more WLAN. Each wireless LAN may be divided into multiple VLANs. In addition, one VLAN can extend over multiple WLANs. In one example, it may be desirable to communicate with a particular logical group of mobile devices. In this case, a VLAN can be set up with those devices as members of the group. Packets addressed to members of this group can have an associated field with an identification or tag of the VLAN contained therein. Ideally, packets with this VLAN identification will only be exchanged with members of the VLAN group. However, where a large number of thin APs are used, and multiple VLANs need to be considered, the switch is required to manage all these AP, WLAN and VLAN combinations, which requires considerable resources in the switch and messaging overhead in the air interface.
Accordingly, what is needed is a technique for a network switch to manage WLANs having many thin APs and covering multiple VLANs. It would also be of benefit to mitigate the replication of unneeded broadcast packets.
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The apparatus and method components have been represented where appropriate by conventional symbols in the drawings, showing only those specific details that are pertinent to understanding the embodiments of the present invention so as not to obscure the disclosure with details that will be readily apparent to those of ordinary skill in the art having the benefit of the description herein.